Superheater



Feb. 4, 1936- H. PEPERKORN 2,029,334

' SUPERHEATER t v I Filed Dec. 14, 1 934 2 Sheets-Sheet 1 ATTORNEYPatented Feb. 4, 1936 UNITED STATES PATENT OFFICE SUPERHEATER HeinrichPeperkorn, Kassel-Wilhelmshohe, Germany, assignor to The superheaterCompany,

New York, N. Y.

Application December 14, 1934, Serial No. 757,433 In Germany February'7, 1934 4 Claims.

pentine superheater elements are located in the 5 return chamber and.are connected to headers in the smoke-box by means of tube lengthsextending through the return fire-tubes. The connecting}. unions areequivalent between the elements and the tube-lengths are duringoperation of the boiler located within the fire-tubes. When an elementis to be removed it becomes necessary to disconnect the forward ends ofthe connecting tubes from the headers and to push thecorrespondingisuperheater element back into the return chamber until theconnection comes to lie within the return chamber and is thereby madeaccessible. In this arrangement the superheater surface is in additionlimited by the fact that suiiicient space must remain free in the returnchamber so that these connections can be reached after the superheaterelement has been pushed back.

As contrasted with this, the present invention consists in giving thesuperheater elements which lie within the return chamber and which areconnected with the lengths extending to the super heater headers, aserpentine form a portion of which lies in the return chamber and theother portion of which extends into the tubes and is there supported.The superheater elements extend into the smoke tubes in accordance withthe invention and it is therefore possible to place sufficientsuperheater surface into this hot zone of the smoke tubes and still tohave enough space in the return chamber to make possible access to theconnections between the leads from the superheater headers and thereturn chamber portions.

It has been suggested heretofore in the case of a superheater whose mainportion lies in the return chamber, to have one or another loop extendinto a smoke tube. This, however, was only done for the purpose ofsupporting this end of the superheater while its other end was securedto the'headers which were located in the return chamber itself and whichhad to be inserted into the return chamber or taken out of it eitherthrough the flue or through a special opening in the rear wall. Theseprior cases therefore were not concerned with the superheater which hasa header in the smoke box of the boiler and which has a superheater ofenlarged surface in the return chamber. An arrangement in accordancewith the present invention has the further advantage that the usualsuperheater installation which has a header or headers located in thesmoke" box and has its elementslying completely within the fire tubescan-readily be changed over into a return chamber superheater withoutdiscarding the header; In this way a new superheater with materiallyhigher superheater temperatures can be supplied at relatively low cost.Even the old tube lengths extending from the superheater header into thefire-tubes and the clamps can be retained for the new superheater.

It is only necessary to le'ngtli'en the tubes by weld- 1 ing on a piece.The new superheater canbe given such form that the numberof connectionsto the headers remainsthe same as inthe usual smoke tube superheatersand that the connecting lengths between the superheater headers and theelements located in the return chamber remain the same for given groupsof elements. A further advantageous characteristic of the newsuperheater is that the drop in steam pressure through the elements iskept low.

The drawings show in Fig. 1 a View partly in lateral elevation andpartly in longitudinal section of a superheater in accordance with theinvention; Fig. 2 is a horizontal section on line 2-2 of Fig. 1; Fig. 3shows a fragmentary horizontal section on an enlarged scale of thereturn chamber portion of the superheater and boiler, the superheaterbeing somewhat modified from the form shown in Figs. 1 and 2; Fig. 4 isa section on line l l of Fig. 3; Fig. 5 is an end view looking from theleft of Fig. 4; Fig. 6 shows a further variation and Figs. 7 and 8 showdetails.

In the form of the invention illustrated in Figs. 1, 2 and 3 the returnchamber of the boiler is indicated by the reference numeral I and thesmoke tubes by reference numeral 2. In the smoke box 3 are located thesuperheater headers 4. The elements of the superheater consist ofseparate parts 5, a portion of which as will be clear from Figs. 1, 2and 3 lies within the return chamber l and the remainder of which lieswithin the tubes 2. The connections between the separate parts 5 and theheaders 4 lying in the smoke box 3 is made by means of the pipe lengths6 and the connecting structures or unions 1. The latter may, by way ofexample, be made as illustrated in Fig. 8 where the nut 8 forces theball end connected to the length 6 into the conical end connected to theseparate portion 5. This union is in a conveniently accessible pointwithin the return chamber 1 as will be seen in Figs. 1 and 2.

The loops of each seprentine element 5 lie in a horizontal plane in theform illustrated in Figs. 1 and 2. They may, however, also lie in avertical in their relative position, they can be providedwith distancepieces 9 (see Fig. 3). i

To replace an element all that needs to be done is to break theconnections 1 and to withdraw the 7 element out of the smoke tubeswhereupon it can be taken out thru the flue l2. For the insertion of anelement the sequence of these steps is reversed. The connections of thelengths 6 to the headers 4 need not be disturbed. As may be seen fromFigs. 1 and 2, there is sufilcient space in the return chamberto makeand break the connecting members 1 and in addition asuflicientsuperheater surface is supplied in a very effective heating gas zone i.e. at a point where the gases enter.

the smoke tubes.

The heating surface inside of the return chamber itself can further beaugmented by giving the pieces which connect the loops lying in twoneighboring smoke tubes a twisted or coiled form; In Figs. 3 to 5, forexample, two turns or coils lying in horizontal planes one above theother are shown for this purpose. In the form according to Fig. 6 thereare also shown two coils but these cross.

The portions extending into the smoke tubes 2 are given supports atsuitable points, for example, they may be supported at the tube entranceby the supports I 0 and may further be kept spaced by distance pieces H,(see Figs. 3,4 and 7).

What I claim is: V p p 1. In apparatus of the class described, thecombination of a return tubular boilerhaving a return chamber, a smokebox and smoke tubes connecting them, superheater headers in the smokebox, tubular superheater elements in the returnchamber, each of saidsuperheater elements comprising a plurality of parallel hair pin loopsconnected to form a continuous steam'path, the loops each located inpart in. the return chamber and in part in the smoke tubes, and tube 7lengths, two to each superheater element, extending through smoke-tubesand connecting the ends of the elements to the headers.

2. Apparatus in accordance with claim 1, the I connections between thelast named tube lengths and the elements being within the returnchamber.

tubular elements being spaced from the rear wall of the return chamberand the connections between the lastnamed tube lengths and the elementsbeing accessible from said space.

4. Apparatus in accordance with claim 1, the hair-pin loops of any givenelement nected to each other by coils.

VI-IEINRICH PEPERKORN.

3. Apparatus in accordance with claim 1, the

being con- 7

